Boeing Co shut down production at a military helicopter plant outside Philadelphia on Friday after a third incident involving foreign objects prompted the Pentagon to issue a corrective action against the company.

The government's multibillion-dollar bailout of Citigroup Inc. requires the giant financial services company to lower loan rates for struggling homebuyers who are behind on their mortgage payments.

Shares of Citigroup Inc. climbed in premarket trading Friday, as the financial giant was said to be looking at selling off pieces of itself -- or the entire company -- to help rebuild investor confidence.

Shares of Hewlett-Packard Co fell more than 7 percent on Tuesday on concerns about weak sales of printer ink and personal computers, fed in part by pessimistic quarterly earnings from one of the company's distributors.

As many as 2,444 employees at ArcelorMittal's steel plant could be laid off indefinitely in January, the company said. The company has notified the United Steelworkers and other stakeholders about the possibility of an "indefinite layoff" at the Porter County plant beginning in the second half of January, ArcelorMittal announced Friday.